SOME CUCKOOS 
nests are sometimes white, and coloured eggs are often 
secretly hidden from prying pard and other egg eaters. 
The New Zealand archipelago once nourished two other 
species of Nestor, both of which are now quite extinct, 
so far as we know, though the recent occurrence of the 
supposed extinct rail, Notornis mantell1, makes us careful 
in making too clear a statement on the point. It seems 
unlikely, however, that we shall ever see again either 
Nestor productus or Nestor norfolcensts. 
THE KOEL 
As a representative, and that a very typical one, of 
the cuckoo tribe we shall select the Oriental koel (Eudy- 
namis orientalis, or honorata as the name apparently 
more correctly runs). This bird, like other cuckoos, 
has what is called a zygodactyle foot ; that is, the toes 
are arranged in twos, one pair being turned forwards 
and the other backwards. The “ great” toe and the 
fourth toe are those which are turned backwards, and the 
result of this is an effective grasping organ, from which 
alone it might be safely inferred that the cuckoos are 
arboreal birds. And yet this generalization is marred 
by the fact that there are cuckoos which pass at least 
a great deal of their time upon the ground, such as the 
American Roadrunner (Geococcyx). That originally 
cuckoos were typical “ insessores ’’? seems however to 
be clear. The koel is at least often to be seen at the 
Gardens, and it is one of the few cuckoos in which the 
two sexes vary greatly in colour. In fact the variation 
in plumage from the cock to the hen is as great as in 
any bird. The cock bird is black and the hen brown, 
with white spots and bars. In our common cuckoo, 
Cuculus canorus, a careful examination shows slight, 
but very slight, differences of colour in the two sexes. 
It has a good strong curved beak and yet, unlike our 
cuckoo, who seems to take a delight in the most bristly 
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